Mobile robots are well known and used routinely by military, law enforcement and security forces. As such they are often used in hazardous situations and in stand-off (remote) locations. Accordingly it would be very useful to provide a mobile robot that can be easily adapted for different uses. As well, it would be useful to provide a mobile robot that is easily serviced. Accordingly a modular mobile robot would be advantageous. As well, it would be advantageous if at least some of the modules were interchangeable between different sized mobile robots to suit particular or unique missions.
Some modular robots have been suggested. For example a U.S. patent application Ser. No. 12/316,311 that was published on Jan. 13, 2011. This application shows a mobile robot with right and left track modules. However, the rest of the robot does not appear to be modular and therefore if other than the track modules needed repair or replacement the robot would likely be out of the field until such work could be done.
Mobile robots are often used for specific tasks and have specific weight and operational requirements for those tasks. For example mobile robots are used in space exploration wherein the weight of the robot may be critical to the mission. In stand-off operations having an arm that can pick up hazardous objects may be useful for such missions.
Mobile robots often include endless tracks, particularly mobile robots for use in unknown terrains or for use in climbing stairs and slopes, or navigating obstacles. Endless tracks, which are usually formed of a belt with a number of cleats disposed transversely to the belt's longitudinal direction, are the ground-contacting portion of some common drive systems for mobile robots. Due to their high traction compared to wheels, endless tracks have found application in many fields, such as mobile robotics, farming, and construction. Further, drive systems employing endless tracks can provide a more versatile set of capabilities than wheeled systems, for tasks such as navigation over rough terrains and obstacle climbing.
However, current tracks have a number of drawbacks. For instance, they can experience more friction than wheels and thus require more power to drive, and may cause vibrations when moving and turning. Further, they may slip off the wheel or sprocket pulley which drives them, possibly damaging the track or the drive mechanism. If this happens in a hazardous situation where the robot is being operated remotely, it may be rendered inoperable. The wheel driving them may also occasionally rotationally slip within the track, causing a loss of locomotive force.
In addition, mobile robots are often deployed in environments whose surface characteristics are unknown a priori, and may be very uneven, irregular or bumpy. In such situations, the probability of the robot falling over after losing its balance can be quite high. For situations where the robot is being operated remotely in a hazardous situation, falling over can render the robot inoperable. Furthermore, it may be required that the mobile robot has the capability to climb obstacles, which is generally a risky task as it can quite easily lead to the robot tipping over.
Therefore, it would be advantageous to provide a device that overcomes the aforementioned difficulties.